Method and System for Authentication and Authorization

2. The method of claim 1, further comprising a step of updating the list of credentials and authorizations at the local computer system in response to the request from the local computer to the central computer system and a step of checking if the requested access can be granted by consulting the updated list of credentials and authorizations.

3. The method of claim 2, wherein access is denied, if the requested access cannot be granted by consulting the updated list of credentials and authorizations.

4. The method of claim 1, further comprising a step of requesting updates to the list of credentials and authorizations from the local computer system to the central computer system in accordance with a time schedule.

5. The method of claim 1, wherein the central computer system is configured for communication with a plurality of local computers systems, each being provided in a private network of separate renewable power plants, the central computer system comprising credentials and authorizations for each of the plurality of local computer systems, wherein the step of communicating a request for update of the list of credentials and authorizations at a specific local computer system comprises a step of filtering of credentials at the central computer system to comprise credentials for the specific private network only.

6. The method of claim 1, wherein the step of requesting access via a computer interface in the component is communicated to a single local computer system in the private network, the single local computer system being configured for handling access to all access restricted component of the renewable power plant.

7. The method of claim 1, wherein the step of updating the list of credentials and authorizations can only be effectuated upon a request from the local computer system.

8. The method of claim 1, wherein the central computer system is encompassed in a second private network of an external data centre.

9. The method of claim 1, wherein the step of communicating the request from the local computer system to the central computer system is carried out at least partly via a public network.

10. The method of claim 2, further comprising a step of validity testing the updated list of credentials and authorizations.

14. The system of claim 12, wherein the updated list of credentials and authorizations is specific to the private network in which the local computer system is arranged.

15. The system of claim 11, wherein the local computer system is the only computer system in the private network configured for handling access and authorization of the components of the power plant.

19. The memory of claim 17, wherein the updated list of credentials and authorizations is specific to the private network in which the local computer system is arranged.

20. The memory of claim 16, wherein the local computer system is the only computer system in the private network configured for handling access and authorization of the components of the power plant.